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Study of Different AM Fungi and Soil Moisture Levels on Component of Yield of Grass

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  • payame noor university of mariwan

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In order to determination of different levels AM fungi and soil moisture on the quantitative and qualitative grass yield, an investigation with three levels of moisture and four level AM fungi in three replication using randomized completely block design was done. This research was achieved in payame noor University, Marivan, Iran. Results from the analysis of variance showed that highly significant difference existing among all traits measured. thus indicating that there is variability in traits studied. Results correlation analysis showed that was high significant and positive correlation with all studied traits. The highest positive correlation in moisture condition were observed between Dry weight of root and Turgid weight of air organ (r = 0.992**). Results correlation analysis in species AM fungi showed Fresh weight of air organ and Turgid weight of air organ (r = .987**), Packed root and Fresh weight of air organ and Turgid weight of air organ & Dry weight of root (r = .986**) Dry weight of root and Fresh weight of air organ (r = .975**).
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Technical Journal of Engineering and Applied Sciences
Available online at www.tjeas.com
©2013 TJEAS Journal-2013-3-1/44-47
ISSN 2051-0853 ©2013 TJEAS
Study of Different AM Fungi and Soil Moisture Levels on Component
of Yield of Grass
Sarkaut Salimi1*, Salaheddin Moradi2 and Anvar Rashid Abdola3
1- Department of Agriculture, Payame Noor University, PO BOX 19395-3697 Tehran, Iran
2- Scientific Assistant, Department of Agriculture, Payame Noor University, PO BOX 19395- 3697
Tehran, Iran
3- Department of Agronomy, Agricultural Technical Institute of Bakrajo, Sulaimani, Iraq
Corresponding author Email: sarkaut1983@gmail.com
ABSTRACT: In order to determination of different levels AM fungi and soil moisture on the
quantitative and qualitative grass yield, an investigation with three levels of moisture and four level
AM fungi in three replication using randomized completely block design was done. This research
was achieved in payame noor University, Marivan, Iran. Results from the analysis of variance
showed that highly significant difference existing among all traits measured. thus indicating that there
is variability in traits studied. Results correlation analysis showed that was high significant and
positive correlation with all studied traits. The highest positive correlation in moisture condition were
observed between Dry weight of root and Turgid weight of air organ (r = 0.992**). Results correlation
analysis in species AM fungi showed Fresh weight of air organ and Turgid weight of air organ (r =
.987**), Packed root and Fresh weight of air organ and Turgid weight of air organ & Dry weight of
root (r = .986**) Dry weight of root and Fresh weight of air organ (r = .975**).
Keywords: AM fungi, Grass, Moisture, yield.
INTRODUCTION
Global change is likely to increase drought periods which could alter global patterns of organic matter
production and decomposition (Feyen and Dankers, 2009). Drought resistance of plant can be defined as the
ability to survive under an unfavourable water deficit. Drought threat has significant consequences for
belowground carbon (C) and nutrient cycling. It may affect soil processes through changes in C allocation to
roots and foliage as well as C turnover in the rhizosphere. Roots and shoots are interrelated in a functional
equilibrium governed by optimal distribution of resources and biomass (Farrar and Jones, 2000). This
equilibrium may bemodified under changing environmental conditions. Water deficit induces a range of
adaptations in plants that favor their growth or survival (Malinowski and Belesky, 2000). These adaptations
include: (i) drought avoidance, which may be due to improved water uptake by an extensive root system,
reduced transpiration losses following stomatal closure (Pe˜nuelas et al., 2004) or water storage in plant tissues
and (ii) drought tolerance and recovery from drought which includes accumulation and translocation of
assimilates, osmotic adjustments or maintenance of cell wall elasticity (Malinowski and Belesky, 2000). The
magnitude and rate of climate change will critically affect the extent to which plants in ecological systems can
withstand stress and their ability to adapt. Stationary organisms such as plants may be the most limited in their
ability to cope with environmental change (Jump and Peˇnuelas, 2005). Environmental conditions such as
temperature, light and water availability play a key role in defining the role and distribution of plants in natural
ecosystems. In addition, the response of plants to an altered environment may depend on their ability to form
symbiotic relationships with microorganisms. In regions such as Iran, water availability may be the most
influential limiting factor for plant growth and nutrient uptake. The IPCC (2007) predicts large climate changes
which may have large implications on water resources and consequently as well as on water management and
agricultural production. Climate change causes a chain of problems, which require integrated approaches.
Because of the economic importance, the functioning and structure of grass ecosystems have been studied
intensively the last decades in temperate regions (Clark et al., 1997). Due to their large extent grasslands play
a major role in environmental issues that are related to agricultural activities, climate change, water balance
studies, etc. (Conijn, 2005). In forage and turf grasses, the molecular basis for stress tolerance remains largely
unknown (Zhang et al., 2006). Arbuscular mycorrhizal fungi (AMF) are plant root symbionts that often help
Tech J Engin & App Sci., 3 (1): 44-47, 2013
2
plants obtain key nutrients such as phosphorus, water, and other soil nutrients by significantly increasing the
plant’s capacity for nutrient uptake (Entry et al., 2002). The relationships between AM colonization and plant
water relations were comprehensively reviewed by Augé (2001), who concluded that AM effects on water
relations included direct effects, as well as effects that were strictly related to changes in plant nutrition and
size. In field situations, size effects can be important in plant survival and success, particularly in species that
avoid rather than tolerate drought. Aualso highlighted the fact that we know very little about variations in
water relations consequent on different plantfungus combinations. However, some recent work has included a
number of different AM fungi in investigations of responses to water stress. Considerable diversity in outcome
has been revealed (Marulanda et al., 2003; Aroca et al., 2007), which may go some way to explaining
apparently contradictory results in earlier investigations. The influence of AM colonization on plant water
relations was first investigated systematically with soybean (Safir et al., 1971, 1972). Results showed that AM
plants had lower resistances to water transport than non-mycorrhizal plants and, in this instance, it appeared
that most of the difference was attributable to changes in root resistance, for shoot resistances were small and
did not differ in the two groups of plants. The conclusion was that the effect was probably due to improved
nutrition, because the differences could be eliminated if nutrients were supplied or fungicide applied (Safir et al.,
1972).
The objective of the study was to assess the impact of AM fungi and soil moisture levels on root morphological
properties of Poa.
MATERIALS AND METHODS
The experiment was carried out in pots, to evaluate the effects of different soil moisture and AM fungi on
poa growth in greenhouse condition at the University of payame noor University, Marivan, Iran. Soil samples
were taken from the top 20 cm. The soil is slightly alkalin and has a sandy texture. After sampling, the soil was
air dried, mixed and passed through a 4-mm sieve. A chemical analysis of soil indicated the content of N, P, K,
Fe, Zn, Cu and Mn to be 140, 7, 155, 5, 0.17, 1.6 and 3.2 mg kg−1 respectively. Volumetric moisture content at
field capacity determined by the method of Richardson and Siccama (2000) was 28. %. Pots were filled with
sandy soil (10 kg) which had been sterilized in an outoclave at 121 °C for 25 minute. Only well-filled, healthy-
looking seeds were used. Four rows of five seeds for each pot were placed in a constant temperature
greenhouse (22 °C). The day/night cycle consisted of 16 h light and 8 h of darkness. Plants were checked daily
and watered, as needed. A factorial experiment was established, including drought effect and AM fungi on root
morphological properties. We used 2 species of AM fungi, G.mosseae and G.intraradices and a mixture of this
two species of AM fungi under three soil moisture levels. For the drought treatment water was withheld to
induce drought conditions and soil moisture was less than 9%. In the medium water treatment, percent soil
moisture ranged 15%. To assure three replicates for each treatment combination, in total 36 pots with planted
soil (two individual AM species and a mixture under three different water levels) and nine pots without AM fungi
(control under three different water levels) were incubated for 60 days. After 60 days of growth under different
moisture regimes, the plants were harvested. Each pots was emptied and roots were separated from the soil
manually. Roots were washed free of soil using a high pressure shower, dried in an oven at 60 ◦C, and
weighed to determine root dry matter (RDM). The data were statistically processed by analysis of variance
according to a randomized complete block design and means with standard errors were calculated using the
program Statistical Analysis System, version 9.1 (SAS Institute, Cary, NC, USA). Differences between the
treatments were determined using Duncan’s test.
RESULTS AND DISCUSSION
Analysis of variance
Results from the analysis of variance (Table 1&2) showed that highly significant difference existing among
all traits measured; thus indicating that there is variability in AM fungi and moisture level studied. thus indicating
that there is variability in traits studied. This result implied that AM fungi and moisture factor effect on
component yield in grass. The soil moisture and AM fungi applied measurements indicated a reasonable
differentiation among the three water level and four species fungi treatments (Table 1&2). The results are in
agreement with (Safir et al., 1972).
Correlation analysis
Knowledge of the relationship among plant characters is useful while selecting traits for yield improvement.
Results correlation analysis showed that was high significant and positive correlation with all studied traits
Tech J Engin & App Sci., 3 (1): 44-47, 2013
3
(Tables 3 & 4). The highest positive correlation in moisture condition were observed between Dry weight of root
and Torjesance weight of air organ (r = 0.992**) and between Packed root & Fresh weight of air organ, Day to
maturity & Plant height (r = 0.987**). Also results showed that Significantly positive correlations were between
Plant height with Fresh weight of root, Plant height & Torjesance weight of air organ, Fresh weight of root &
Length root (r = 0.986**), Fresh weight of root & Torjesance weight of (r = 0.984**). Also showed that all traits
had high significant and negative correlation with Day to maturity. Results correlation analysis in species AM
fungi showed Fresh weight of air organ and Torjesance weight of air organ (r = .987**), Packed root and Fresh
weight of air organ and Torjesance weight of air organ & Dry weight of root (r = .986**) Dry weight of root and
Fresh weight of air organ (r = .975**). Also showed that Day to maturity Significantly negative correlations with
all traits. In general a significant positive correlation was observed between most of the traits. However,
negative correlation was also found among certain characters in the present study.
Table 1. Analysis of variance (RCBD) for studied traits in grass under moisture condition
MS
S.O.V
df
Day to
maturity
Plant
height
Fresh
weight of
root
Dry weight
of root
Length
root
Fresh weight
of air organ
Dry weight of
air organ
Turgid
weight
Block
2
0/778
1.174
.001
.000
.488
.001
0/00004
.000
moisture
2
102.778**
96.234**
.139**
.011**
19.781**
.088**
.004**
.124**
Error
4
0/444
.436
.001
0/00005
.409
.000
.000
.000
%CV
8/64
22/38
13/98
8/49
16/72
2/42
2/77
17/83
*&** significantly different at %5 and %1 probability level
Table 2. Analysis of variance (RCBD) for studied traits in grass under AM fungi
MS
S.O.V
df
Day to
maturity
Plant
height
Fresh
weight of
root
Dry weight
of root
Length
root
Packed
root
Fresh
weight of air
organ
Dry weight
of air organ
Torjesance
weight of air
organ
Block
2
2.333**
1.191
.001
0/00002
1.358
.043
.001*
.003
.000
fungi
3
71.194**
52.230**
.093**
.012**
18.301**
2.294**
.085**
.004ns
.114**
Error
6
.111
1.493
.001
.000
.404
.017
.000
.001
0/00009
%CV
8/64
22/38
13/98
8/49
16/72
7/96
2/42
2/77
17/83
*&** significantly different at %5 and %1 probability level
Table 3. Correlation analysis of agronomic traits in grass under moisture condition
Traits name
Day to
maturity
Plant
height
Fresh
weight of
root
Dry
weight of
root
Length
root
Packed
root
Fresh
weight of
air organ
Dry weight
of air
organ
Torjesance
weight of air
organ
Day to maturity
1
Plant height
-.987**
1
Fresh weight of
root
-.983**
.986**
1
Dry weight of
root
-.977**
.969**
.976**
1
Length root
-.972**
.965**
.986**
.962**
1
Packed root
-.922**
.930**
.965**
.965**
.961**
1
Fresh weight of
air organ
-.947**
.954**
.975**
.975**
.954**
.987**
1
Dry weight of
air organ
-.927**
.907**
.943**
.969**
.951**
.972**
.955**
1
Torjesance
weight of air
organ
-.984**
.986**
.984**
.992**
.959**
.952**
.973**
.940**
1
Tech J Engin & App Sci., 3 (1): 44-47, 2013
4
Table 4. Correlation analysis of agronomic traits in grass under AM fungi
Traits name
Day to
maturity
Plant
height
Fresh
weight of
root
Dry
weight of
root
Length
root
Packed
root
Fresh
weight of
air organ
Dry weight
of air
organ
Torjesance
weight of air
organ
Day to maturity
1
Plant height
-.928**
1
Fresh weight of
root
-.945**
.887**
1
Dry weight of
root
-.891**
.856**
.785**
1
Length root
-.905**
.869**
.800**
.927**
1
Packed root
-.858**
.819**
.771**
.962**
.967**
1
Fresh weight of
air organ
-.876**
.855**
.789**
.975**
.949**
.986**
1
Dry weight of
air organ
-.842**
.821**
.753**
.948**
.946**
.966**
.940**
1
Torjesance
weight of air
organ
-.928**
.914**
.823**
.986**
.947**
.962**
.987**
.937**
1
Shading increased soybean plant height and decreased stem diameter, so that 75% shade had the highest
plant height and the lowest stem diameter (Table 2). These results are compatible with those observed in green
gram and groundnut (Singh, 1997), soybean (Huang et al., 1993) and garden pea (Akhter et al, 2009). Haque
et al., (2009) reported that bottle gourd plant exhibited the longest internode at 50% PAR level (20.86 cm) and
the shortest length (17.17 cm) was obtained under full sunlight. This was probably due to higher apical
dominance under shade condition (Hillman, 1984). Plant height and gibberellin concentration increase
progressively when light intensity decreases (Potter et al, 1999). Main stem diameter was also adversely
affected by reduced PAR levels. The highest stem diameter was recorded from 100% as well as 75% PAR
levels, but the lowest diameter was obtained from 25% PAR (Haque et al., 2009). Corre (1983) reported that
stem length increases at the expense of root growth and stem girth.
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We used a novel, nonintrusive experimental system to examine plant responses to warming and drought across a climatic and geographical latitudinal gradient of shrubland ecosystems in four sites from northern to southern Europe (UK, Denmark, The Netherlands, and Spain). In the first two years of experimentation reported here, we measured plant cover and biomass by the pinpoint method, plant 14C uptake, stem and shoot growth, flowering, leaf chemical concentration, litterfall, and herbivory damage in the dominant plant species of each site. The two years of approximately 1C experimental warming induced a 15% increase in total aboveground plant biomass growth in the UK site. Both direct and indirect effects of warming, such as longer growth season and increased nutrient availability, are likely to be particularly important in this and the other northern sites which tend to be temperature-limited. In the water-stressed southern site, there was no increase in total aboveground plant biomass growth as expected since warming increases water loss, and temperatures in those ecosystems are already close to the optimum for photosynthesis. The southern site presented instead the most negative response to the drought treatment consisting of a soil moisture reduction at the peak of the growing season ranging from 33% in the Spanish site to 82% in The Netherlands site. In the Spanish site there was a 14% decrease in total aboveground plant biomass growth relative to control. Flowering was decreased by drought (up to 24% in the UK and 40% in Spain). Warming and drought decreased litterfall in The Netherlands site (33% and 37%, respectively) but did not affect it in the Spanish site. The tissue P concentrations generally decreased and the N/P ratio increased with warming and drought except in the UK site, indicating a progressive importance of P limitation as a consequence of warming and drought. The magnitude of the response to warming and drought was thus very sensitive to differences among sites (cold-wet northern sites were more sensitive to warming and the warm-dry southern site was more sensitive to drought), seasons (plant processes were more sensitive to warming during the winter than during the summer), and species. As a result of these multiple plant responses, ecosystem and community level consequences may be expected.
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Vesicular-arbuscular mycorrhizal fungi can affect the water balance of both amply watered and droughted host plants. This review summarizes these effects and possible causal mechanisms. Also discussed are host drought resistance and the influence of soil drying on the fungi.
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Improvement in stress tolerance of forage and turf grasses is a major breeding goal. Most forage and some turf grasses are grown on marginal lands under stressful environments with minimal inputs. In contrast, current high-input turf grass production systems such as golf courses and lawns are expensive and often environmentally unfriendly. Cultivars with improved stress tolerance are necessary for the development of sustainable and environmentally friendly production systems. Until recently, decades of breeding and selection have resulted in limited improvements of stress tolerance of forage and turf grass species. Recent developments in molecular and genomic sciences suggest new methods to improve stress tolerance in many plants, but compared to major crop plants (e.g., rice [Oryza sativa L.], wheat [Triticum spp.], and maize [Zea mays L.]), the development of molecular and genomic resources for forage and turf grasses has been limited. In this review, we present an overview of recent molecular and genomic studies aimed at improving stress tolerance of forage and turf grasses, including endophyte grass interactions. Important molecular and genomic resources are now available for some forage and turf grasses, including ryegrasses (Lolium spp.) and fescues (Festuca spp.). Noteworthy progress is being made in improvements of both biotic and abiotic stress tolerances of these grasses, but the challenge is to simplify and streamline the molecular tools and new discoveries for cost-effective and efficient application in forage and turf grass breeding. Stress tolerances of many forage and turf grasses are influenced by their mutualistic association with Neotyphodium spp. endophytes, and this area of research is discussed.